The present invention relates to a quick connect fluid coupling having a self-contained releasable collet retainer.
Quick connect couplings are used to quickly and securely connect a tube within a housing bore or to a second tube. Quick connect couplings are utilized in most modern vehicles to connect brake lines, air conditioning lines, power steering lines and other high-pressure and vacuum lines.
In standard quick connect couplings a retainer is received within a female housing bore. The retainer has a plurality of arms which extend radially inwardly in a direction moving axially into the bore. The tube has a radially greater bead which moves into the bore and flexes the arms outwardly. The axially and radially innermost ends of the arms define an inner diameter approximately equal to the other diameter of the tube at locations other than the bead. As the tube is inserted further into the bore, the bead forces the arms radially outwardly, and moves axially past the arms. Once the bead has moved axially beyond the arms, the arms spring back to a position where they are radially outwardly of the tube, and axially between the tube bead and outer end of the bore. The tube is then fully inserted, and the retainer securely retains the tube within the housing.
While quick connect couplings having flexible arms that latch behind the bead are widely used, they do have some deficiencies. The retainers only secure the tube at the circumferentially spaced locations of the legs. Because of the limited contact area, the operation of this type of retainer is highly dependent on the material, length, angle, thickness, and the number of arms. Also, temperature extremes diminish the effectiveness of the arms as they become brittle when cold and softened when hot. Further the flexible arms trap the tube in the connector, but do not offer side load support to the coupling. Further the flexible arms require a relatively large insertion distance because the tube bead must be inserted past the flexible arms.
Sometimes one may wish to remove a tube after insertion. The prior art has proposed release tools to assist in removal. Essentially, the prior art tools are sleeves that slide along the tube. Upon axial inward movement of the release tool, the retainer legs are deflected outwardly to permit separation of the tube and housing.
The use of collet retainer, generally comprising a ring having a split, has been proposed to retain the tube within the housing. The collet is expanded radially by the tube bead upon insertion of the tube into the housing. The collet contracts onto the tube behind the tube bead to retain the tube within the housing. These retainers address some of the deficiencies with the above-described retainers having the spaced legs. However, the proposed collet retainers have not been easily releasable and have not included release tools.